I have created a function to get sms message from db using ajax get call and after success i want to replace the {order_id} text to order-id like 454574 and may b few more variables like customer name etc.
MY TRY
$(document).delegate('.sms-template', 'click', function() {
  var tempID = $(this).attr('id').replace('sms-template-','');
  var oID = $(this).attr('data-id').replace('sms-template-','');
  $.ajax({
    url: 'index.php?route=sale/order/getSmsTemplate&token=<?php echo $token; ?>&template_id='+tempID, 
    type: 'get',
    dataType: 'json',          
    success: function(json) {
        $('textarea#input-order-comment-'+oID).append(json['message']);
    },
    error: function(xhr, ajaxOptions, thrownError) {
        alert(thrownError + "\r\n" + xhr.statusText + "\r\n" + xhr.responseText);
    }
  });
});
It works fine and display message in textarea as
Dear {customer_name}, Your Order : {order_id} is successfully placed and ready to process. 
i want to replace {customer_name} & {order_id} with its number which i have stored in php variable.
PS: I don't have much knowledge of RegEx.